“I am angry and I am frustrated that BP has been unable to stop this oil from leaking and to stop the pollution from spreading,” Mr Salazar said after visiting BP’s US headquarters in Houston. “We are 33 days into this effort and deadline after deadline has been missed.”

President Barack Obama’s administration is facing growing public and political pressure to take full charge of the oil spill containment operation as criticism of BP grows. “If we find they’re not doing what they’re supposed to be doing, we’ll push them out of the way
appropriately,” Mr Salazar said, but he did not specify at what point this would occur or what might be the trigger for it. He added that BP had agreed to pay clean-up costs beyond the $75 million liability limit set by current US law.

BP was also accused yesterday of agreeing to keep a test valve on the Deepwater Horizon oil rig, which later exploded, despite knowing that it would increase the risk of accidents.

the oil flow, according to a letter leaked to the Washington Post.

A representative of BP reportedly signed a copy of the letter, which included wording saying that, by doing so, BP accepted this strategy would “reduce the built-in redundancy” of the blowout preventer, “thereby potentially increasing the contractor’s risk profile”.

BP denied responsibility for keeping the blowout preventer, which failed when the rig exploded on April 20. A spokesman said that Transocean was responsible for all modifications.